Device and method for measuring depth of object

ABSTRACT

A method, by an augmented reality device, of measuring a depth of an object includes determining, from a dot-pattern and a surface-pattern, a pattern of light to be emitted for measuring the depth of the object, identifying, from within an entire area of a pattern generator, a partial area of a light source unit corresponding to an area for the determined pattern, emitting light through the area for the determined pattern, by activating the identified partial area of the light source unit, receiving light reflected from the object; and measuring the depth of the object based on the emitted light and the received reflected light.

TECHNICAL FIELD

The disclosure generally relates to a device and method for measuring adepth of an object, and more particularly, to a device and method formeasuring a depth of an object by using a plurality of types ofpatterned light.

BACKGROUND ART

In order to model a three-dimensional space, depth information about acorresponding space is required. In order to identify such depthinformation, a Time of Flight (ToF) depth camera may be used. Depthcameras may obtain depth information corresponding to a distance betweenan object in the photographed space and a depth camera.

There is growing interest in spatial augmentation techniques in whichthree-dimensional-based interactive elements are added to a space, suchas augmented reality (AR). The core of spatial augmentation techniquesis a three-dimensional space modeling using a depth camera. Using thespatial augmentation techniques, three-dimensionalized reality elementshave three-dimensional position information in space and may interactwith a virtual object.

In this augmented reality field, weight reduction of a device isimportant, and accordingly, there is a demand for a technology forreducing device's power consumption when measuring depth information ofobjects.

DESCRIPTION OF EMBODIMENTS Technical Problem

Provided are a device and method for measuring a depth of an object byselectively using a plurality of types of patterned light.

Also provided is a device and method for measuring a depth of an object,which are capable of dividing a pattern generator into an area fordot-patterned light and an area for surface-patterned light, andemitting the dot-patterned light and the surface-patterned light byusing the divided areas.

Also provided is a device for measuring a depth of an object, which iscapable of reducing power consumption of the device by partiallyactivating a light source for emitting patterned light.

Technical Solution to Problem

In accordance with an aspect of the disclosure, there is provided amethod, by an augmented reality (AR) device, of measuring a depth of anobject includes determining, from a dot-pattern and a surface-pattern, apattern of light to be emitted for measuring the depth of the object,identifying, from within an entire area of a pattern generator, apartial area of a light source unit corresponding to an area for thedetermined pattern, emitting light through the area for the determinedpattern, by activating the identified partial area of the light sourceunit, receiving light reflected from the object; and measuring the depthof the object based on the emitted light and the received reflectedlight.

In accordance with an aspect of the disclosure, there is provided an ARdevice for measuring a depth of an object. The AR device includes alight source unit configured to irradiate light for depth measurement, apattern generator configured to change the irradiated light to patternedlight, a light receiver configured to receive light reflected from anobject in a vicinity of the AR device, a memory storing instructions;and a processor configured to execute the instructions to: determine,from a dot-pattern and a surface-pattern, a pattern of light to beemitted for measuring the depth of the object, identify, from within anentire area of the pattern generator, a partial area of the light sourceunit corresponding to an area for the determined pattern, emit lightthrough the area for the determined pattern, by activating theidentified partial area of the light source unit, receive, through thelight receiver, light reflected from the object, and measure the depthof the object based on the emitted light and the received reflectedlight.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating an example in which an augmentedreality (AR) device measures a depth of an object by emittingdot-patterned light and surface-patterned light according to anembodiment;

FIG. 2 is a block diagram of an AR device according to an embodiment;

FIG. 3 is a block diagram of a depth sensing unit according to anembodiment;

FIG. 4A is a diagram illustrating an example of surface-patterned lightaccording to an embodiment;

FIG. 4B is a diagram illustrating an example of dot-patterned lightaccording to an embodiment;

FIG. 5A is a diagram illustrating an example in which light irradiatedfrom a light source unit is changed to dot-patterned light by a patterngenerator according to an embodiment;

FIG. 5B is a diagram illustrating an example in which light irradiatedfrom a light source unit is changed to surface-patterned light by apattern generator according to an embodiment;

FIG. 6 is a diagram illustrating a matching relationship betweensub-areas of a pattern generator and areas of a real space according toan embodiment;

FIG. 7A is a diagram illustrating an example of emitting dot-patternedlight through one sub-area among sub-areas of a pattern generatoraccording to a position of an object, according to an embodiment;

FIG. 7B is a diagram illustrating an example of emitting dot-patternedlight through two sub-areas among sub-areas of a pattern generatoraccording to a position of an object, according to an embodiment;

FIG. 8 is a flowchart of a method, performed by an AR device, forselectively emitting dot-patterned light and surface-patterned lightaccording to an embodiment;

FIG. 9 is a flowchart of a method, performed by an AR device, forsequentially emitting dot-patterned light and surface-patterned lightaccording to an embodiment;

FIG. 10 is a diagram illustrating an example of emitting patterned lightin a partial area in the vicinity of a point of gaze of a user accordingto an embodiment;

FIG. 11 is a flowchart of a method for emitting patterned lightaccording to a depth of a point of gaze of a user; according to anembodiment;

FIG. 12 is a diagram illustrating an example of emitting patterned lightin response to a user's gesture being detected according to anembodiment;

FIG. 13 is a flowchart of a method for emitting patterned light inresponse to a user's gesture being detected according to an embodiment;and

FIG. 14 is a flowchart of a method for measuring a depth of thesurroundings of an AR device according to a change in a depth of a pointof gaze according to an embodiment.

MODE OF DISCLOSURE

Throughout the disclosure, the expression “at least one of a, b or c”indicates only a, only b, only c, both a and b, both a and c, both b andc, all of a, b, and c, or variations thereof.

Hereinafter, embodiments of the disclosure will be described in detailwith reference to the accompanying drawings for those of ordinary skillin the art to easily implement the embodiments. However, it should beunderstood that the disclosure is not limited to embodiments describedherein and may be embodied in different ways. In addition, portionsirrelevant to the description are omitted from the drawings for clarity,and like components are denoted by like reference numerals throughoutthe specification.

Throughout the specification, when an element is referred to as being“connected to” another element, the element gray be “directly connectedto” the other element, or the element may also be “electricallyconnected to” the other element with an intervening elementtherebetween. In addition, when an element is referred to as “including”or “comprising” another element, unless otherwise stated, the elementmay further include or comprise yet another element rather than precludethe yet other element.

In the disclosure, the term augmented reality (AR) may refer to showinga virtual image or both a real world object and a virtual image in aphysical environment space of the real world.

Furthermore, the term augmented reality device/AR device may refer to adevice that may express AR, and generally includes not only AR glassesin the form of glasses worn on a facial area by a user, but also a headmounted display (HMD) apparatus worn on a head area or an AR helmet.

Meanwhile, the term “real scene” may refer to a scene of the real worldthat a user sees through the AR device, and may include a real worldobject. Also, the term “virtual image” may refer to an image generatedvia an optical engine and may include both a static image and a dynamicimage. Such a virtual image is observed along with a real scene, and maybe an image representing information about a real world object in thereal scene, information about an operation of an AR device, a controlmenu, or the like.

Thus, general AR devices may include an optical engine for generating avirtual image based on light generated from a light source, and awaveguide which guides the virtual image generated by the optical engineto a user's eyes and is formed of a transparent material so that theuser may also see a scene of the real world as well. As described above,the AR devices should be capable of observing a scene of the real worldas well, and thus, include an optical element for changing an opticalpath having straightness basically in order to guide light generatedfrom the optical engine to a user's eyes through the waveguide. In thiscase, an optical path may be changed using reflection by a mirror or thelike, or the optical path may be changed via diffraction by adiffractive element such as a diffractive optical element (DOE), aholographic optical element (HOE), or the like, but the disclosure isnot limited thereto.

In the disclosure, an AR device may measure a depth of an object byusing a depth sensor. The AR device may emit light toward the object byusing an active sensor. The active sensor may include a device thatincludes a source, emits light from a light source, light, pulse, or thelike onto a subject, and receives information reflected from thesubject. Unlike a passive sensor, the active sensor includes its ownlight source and actively emits light from the light source onto asubject, and may measure back scattering of light reflected from thesubject to the active sensor. For example, the active sensor may includea ToF sensor for calculating the time taken for a laser or infraredlight to return after the laser or the infrared light is emitted onto asubject, a laser sensor, a microwave sensor, a structured light sensorfor calculating a distance based on a size or shape of an image on asubject by emitting specific patterned light, and an invertible lightsensor.

In the disclosure, a pattern generator is a configuration for changinglight irradiated from a light source to patterned light, and mayinclude, for example, a DOE or a liquid crystal (LC) lens array. Lightirradiated from a light source to the pattern generator may be changedto patterned light while passing through the pattern generator, andthus, the patterned light may be emitted from the pattern generator. Thepattern generator may include a dot-patterned light generation area forchanging light irradiated from a light source to dot-patterned light anda surface-patterned light generation area for changing light irradiatedfrom a light source to surface-patterned light.

In the disclosure, surface-patterned light may refer to patterned lightemitted toward an entire area including an object, and for example, maybe emitted toward an entire area including an object without an areaomitted from the area including the object.

Also, dot-patterned light may be patterned light emitted toward apartial area within an area including an object, and may include, forexample, pieces of dot-shaped light spaced apart from each other by acertain distance.

Hereinafter, embodiments of the disclosure will be described in detailwith reference to the accompanying drawings.

FIG. 1 is a diagram illustrating an example in which an AR device 1000measures a depth of an object by emitting dot-patterned light andsurface-patterned light, according to an embodiment.

The AR device 1000 may measure a depth of an object by emittingpatterned light and receiving patterned light reflected from the objectin order to measure the depth of the object. The AR device 1000 may emitsurface-patterned light to measure a depth of an object located at ashort distance from a user. For example, the AR device 1000 emitssurface-patterned light to measure a depth of the surroundings of auser's hand located at a short distance therefrom, and thus, mayeffectively identify a gesture of the user's hand. Also, the AR device1000 may emit dot-patterned light to measure a depth of an objectlocated at a long distance from a user. For example, the AR device 1000emits dot-patterned light to measure a depth of the surroundings of asofa located at a long distance therefrom, and thus, may generate adepth map of the surroundings of the sofa.

The AR device 1000 may divide an entire area of a pattern generatordescribed below into an area for surface-patterned light and an area fordot-patterned light, and may emit the surface-patterned light and thedot-patterned light by selectively utilizing the divided areas. The ARdevice 1000 may reduce an amount of power consumed to measure depths ofobjects located at a short distance therefrom and a long distancetherefrom, by effectively controlling emission of the surface-patternedlight and emission of the dot-patterned light.

FIG. 2 is a block diagram of the AR device 1000 according to anembodiment.

Referring to FIG. 2 , the AR device 1000 may include a user input unit1100, a camera module 1200, an image output unit 1300, a communicationinterface 1400, a depth sensing unit 1500, a gaze tracking sensor 1600,a storage 1700, and a processor 1800.

The user input unit 1100 refers to a member for inputting data for auser to control the AR device 1000. For example, the user input unit1100 may include, but is not limited to, at least one of a keypad, adome switch, a touch pad (a touch capacitive type, a pressure resistivetype, an infrared beam sensing type, a surface acoustic wave type, anintegral strain gauge type, a piezoelectric effect type, or the like), ajog wheel, or a jog switch. The user input unit 1100 may receive a userinput for measuring a depth of an object. Also, the AR device 1000 mayreceive an input of a user's voice via a microphone (not shown).

The camera module 1200 may capture an image of surroundings of the ARdevice 1000. The camera module 1200 may obtain an image frame such as astill image or a moving image through an image sensor when anapplication that requires a shooting function is executed. An imagecaptured through the image sensor may be processed by the processor 1800or a separate image processing unit (not shown), The camera module 1200may include, for example, an RGB camera module, but is not limitedthereto. An RGB image captured by the camera module 1200 may be utilizedto measure a depth of an object in the vicinity of the AR device 1000.

The image output unit 1300 displays and outputs information processed bythe AR device 1000. For example, the image output unit 1300 may outputinformation related to a service provided based on a user interface formeasuring a depth of an object in the vicinity of the AR device 1000 andan image obtained by capturing surroundings of the AR device 1000.

According to an embodiment of the disclosure, the image output unit 1300may provide an AR image. The image output unit 1300 according to anembodiment of the disclosure may include an optical engine and awaveguide. The optical engine may project light of a virtual image to bedisplayed toward the waveguide. The optical engine may include an RGBlight source and an image panel. The RGB light source is an opticalcomponent that illuminates light, and may generate light by adjustingthe RGB color. The RGB light source may include, for example, alight-emitting diode (LED). The image panel may include a reflectiveimage panel that modulates light illuminated by the RGB light sourceinto light including a two-dimensional image and reflects the light. Thereflective image panel may be, for example, a digital micromirror device(DMD) panel or a liquid crystal on silicon (LCoS) panel, or may be orother known reflective image panels.

Also, a virtual image projected from the optical engine onto thewaveguide may be reflected in the waveguide according to a totalreflection principle. An optical path of the virtual image projectedonto the waveguide is changed by a diffraction grating formed in aplurality of areas, and the virtual image may be finally output to auser's eyes. The waveguide may function like a light guide plate thatchanges an optical path of a virtual image. In an embodiment, becausethe waveguide is formed of a transparent material, a user may not onlysee a virtual object of a virtual image totally reflected through thewaveguide, but also see an external real scene, and thus, a waveguidemay be referred to as a see-through display. The image output unit 1300may provide an AR image by outputting a virtual image through thewaveguide.

The communication interface 1400 may transmit and receive, to and froman external device (not shown) or a server (not shown), data forreceiving a service based on an image obtained by capturing an image ofsurroundings of the AR device 1000.

The depth sensing unit 1500 may be controlled by the processor 1800described below to measure a depth of an object in the vicinity of theAR device 1000. The depth sensing unit 1500 may include a light sourceunit 1510, the pattern generator 1520, and a light receiver 1530, and astructure and operation of the depth sensing unit 1500 will be describedin detail with reference to FIG. 3 .

The gaze tracking sensor 1600 may track gaze of a user wearing the ARdevice 1000. The gaze tracking sensor 1600 may be installed in adirection toward a user's eyes, and may obtain gaze information relatedto gaze of the user. The gaze tracking sensor 1600 may include, forexample, at least one of an IR scanner or an image sensor, and when theAR device 1000 is a device in the form of glasses, a plurality of gazetracking sensors may be respectively arranged in the vicinity of a leftwaveguide and a right waveguide of the AR device 1000 toward a user'seyes.

The gaze tracking sensor 1600 may detect data related to gaze of auser's eyes. The user's gaze information gray be generated based on thedata related to the gaze of the user's eyes. The gaze information isinformation related to gaze of a user, and may include, for example,information about positions of the pupils of the user's eyes,coordinates of central points of the pupils, a direction of the gaze ofthe user, and the like. The direction of the gaze of the user may be,for example, a gaze direction from the central points of the user'spupils toward a position at which the user gazes. The gaze informationgenerated by the gaze tracking sensor 1600 may be used to identify aposition and depth of a point of the gaze of the user.

The storage 1700 may store programs to be executed by the processor 1800described below, and may store data that is input to or output from theAR device 1000.

The storage 1700 may include at least one of a flash memory type storagemedium, a hard disk type storage medium, a multimedia card micro typestorage medium, card type memory (for example, secure digital (SD)memory, eXtreme Digital (XD) memory, or the like), random access memory(RAM), static random access memory (SRAM), read-only memory (ROM),electrically erasable programmable read-only memory (EEPROM),programmable read-only memory (PROM), magnetic memory, a magnetic disk,or an optical disk.

The programs stored in the storage 1700 may be classified into aplurality of modules according to their functions, and may include, forexample, a light pattern selection module 1710, an emission rangedetermination module 1720, a light source control module 1730, a depthinformation generation module 1740, and a gaze point identificationmodule 1750.

The processor 1800 controls overall operations of the AR device 1000.For example, by executing the programs stored in the storage 1700, theprocessor 1800 may generally control the user input unit 1100, thecamera module 1200, the image output unit 1300, the communicationinterlace 1400, the depth sensing unit 1500, the gaze tracking sensor1600, the storage 1700, and the like.

The processor 1800 may select a type of patterned light to be emittedthrough the pattern generator 1520 by executing the light patternselection module 1710 stored in the storage 1700. The processor 1800 mayselect a pattern of light emitted through the generator 1520. Theprocessor 1800 may determine whether to emit dot-patterned light orsurface-patterned light based on a distance between an object for whichdepth is to be measured and an AR device.

The processor 1800 may determine to emit dot-patterned light when adistance between an AR device and an object where a point of gaze of auser is directed is greater than or equal to a certain threshold value.For example, the processor 1800 may identify a depth of a point of gazeof a user by using the gaze tracking sensor 1600 described below, anddetermine to emit dot-patterned light when the depth of the point of thegaze of the user is greater than a threshold value. Also, for example,the processor 1800 may identify a depth of a point of gaze of a user byusing the gaze tracking sensor 1600 described below, and determine toemit surface-patterned light when the depth of the point of the gaze ofthe user is less than a threshold value.

Alternatively, for example, the processor 1800 may first measure a depthof a certain area in the vicinity of a position where a point of gaze ofa user is directed, and determine to emit dot-patterned light when themeasured depth is greater than a threshold value. Alternatively, forexample, the processor 1800 may first measure a depth of a certain areain the vicinity of a position where a point of gaze of a user isdirected, and determine to emit surface-patterned light when themeasured depth is less than a threshold value.

The processor 1800 may determine to emit dot-patterned light when it isnecessary to scan the surroundings of the AR device 1000. For example,when the AR device 1000 is powered on, the processor 1800 may determineto emit dot-patterned light in order to generate a depth map forneighboring objects. Also, for example, when a depth of a point of gazeof a user significantly changes to be greater than or equal to a certainthreshold value, the processor 1800 may determine to emit dot-patternedlight in order to generate a depth map for neighboring objects.

When it is necessary to identify an input of a user's gesture, theprocessor 1800 may determine to emit surface-patterned light. Forexample, when a certain gesture action by a user's hand is detected, theprocessor 1800 may determine to emit surface-patterned light in order toreceive an input of a gesture of the user's hand.

The processor 1800 may detect a gesture of a user's hand, determine toemit surface-patterned light onto an area in the vicinity of the user'shand, and determine to emit dot-patterned light onto the remaining area.

The processor 1800 may determine an emission range for emittingpatterned light by executing the emission range determination module1720 stored in the storage 1700.

When it is determined to emit dot-patterned light, the processor 1800may determine an emission range for emitting the dot-patterned light,and identify a light source corresponding to a dot-patterned lightgeneration area of the pattern generator 1520. The processor 1800 mayidentify a portion of the light source unit 1510 corresponding to theentire dot-patterned light generation area. When the emission range foremitting the dot-patterned light is a partial area of a real space, theprocessor 1800 may select a sub-area of the dot-patterned lightgeneration area, and may also select a portion of the light source unit1510 corresponding to the selected sub-area.

When it is determined to emit surface-patterned light, the processor1800 may determine an emission range for emitting the surface-patternedlight, and identify a light source corresponding to a surface-patternedlight generation area of the pattern generator 1520. Also, the processor1800 may identify a portion of the light source unit 1510 correspondingto the entire surface-patterned light generation area. When the emissionrange for emitting the surface-patterned light is a partial area of areal space, the processor 1800 may select a sub-area of thesurface-patterned light generation area, and may also select a portionof the light source unit 1510 corresponding to the selected sub-area.

The processor 1800 may determine to emit the patterned light only for apartial area within an entire area in the vicinity of the AR device1000, according to a preset criterion. For example, the processor 1800may determine the emission range of the patterned light by considering atype of an application being executed and a function of the application.For example, in order to identify the user's gesture, the processor 1800may determine a partial area in the vicinity of the user's hand as anarea onto which the patterned light is to be emitted. However, thedisclosure is not limited thereto, and for example, the emission rangeof the patterned light may be determined according to various criteriasuch as a remaining battery amount of the AR device 1000, a batteryconsumption for measuring a depth, and an accuracy of a depth to bemeasured.

Also, when a point of gaze of a user is identified by the gaze pointidentification module 1750 described below, the processor 1800 maydetermine a certain area in the vicinity of the point of the gaze of theuser as an area onto which patterned light is to be emitted.

The processor 1800 may allow patterned light to be emitted through atleast a portion of the pattern generator 1520 by executing the lightsource control module 1730 stored in the storage 1700.

The processor 1800 may determine through which area of the patterngenerator 1520 the patterned light should be emitted based on the typeof the patterned light and the emission range of the patterned light.The processor 1800 may determine a pattern of the light to be emittedand emission range of the light to be emitted, and may determine throughwhich area of the pattern generator 1520 the light should be emitted.Also, the processor 1800 may activate a partial area of the light sourceunit 1510 corresponding to a partial area of the pattern generator 1520,so that patterned light is emitted through the partial area of thepattern generator 1520.

The processor 1800 may activate a portion of the light source unit 1510corresponding to a dot-patterned light generation area, so that lightirradiated from the portion of the light source unit 1510 may be emittedthrough the dot-patterned light generation area of the pattern generator1520. The light emitted through the dot-patterned light generation areamay be dot-patterned light. Also, the processor 1800 may receive thedot-patterned light reflected from an object. The dot-patterned lightemitted from the dot-patterned light generation area may be reflectedfrom the object, and the light receiver 1530 of the AR device 1000 mayreceive the reflected dot-patterned light.

The processor 1800 may activate a portion of the light source unit 1510corresponding to a surface-patterned light generation area, so thatlight irradiated from the portion of the light source unit 1510 may beemitted through the surface-patterned light generation area of thepattern generator 1520. The light emitted through the surface-patternedlight generation area may be surface-patterned light. Also, theprocessor 1800 may receive the surface-patterned light reflected from anobject. The surface-patterned light emitted from the surface-patternedlight generation area may be reflected from the object, and the lightreceiver 1530 of the AR device 1000 may receive the reflectedsurface-patterned light.

Meanwhile, the processor 1800 may control the light source unit 1510 sothat surface-patterned light and dot-patterned light are sequentiallyemitted in order to scan the surroundings of the AR device 1000. In thiscase, the processor 1800 may repeat an operation of activating a portionof the light source unit 1510 corresponding to a dot-patterned lightgeneration area of the pattern generator 1520 to emit dot-patternedlight, and then, activating a portion of the light source unit 1510corresponding to a surface-patterned light generation area of thepattern generator 1520 to emit surface-patterned light. Also, theprocessor 1800 may determine whether to terminate scanning ofsurroundings of the AR device 1000 based on a result of measuring adepth by the depth information generation module 1740 described below.When it is determined that a depth map is sufficiently generated, theprocessor 1800 may terminate scanning of the surroundings of the ARdevice 1000.

The processor 1800 may measure a depth of an object by executing thedepth information generation module 1740 stored in the storage 1700. Theprocessor 1800 may measure a depth of an object based on emitteddot-patterned light and reflected dot-patterned light. For example, theprocessor 1800 may calculate a depth of an object based on a time whendot-patterned light is emitted, a time when the reflected dot-patternedlight is received, a pattern of the emitted dot-patterned light, and apattern of the received dot-patterned light. Also, the processor 1800may generate a depth map of the surroundings of the AR device 1000 basedon the calculated depth of the object.

The processor 1800 may measure a depth of an object based on emittedsurface-patterned light and reflected surface-patterned light. Theprocessor 1800 may calculate a depth of an object based on a time whensurface-patterned light is emitted, a time when the reflectedsurface-patterned light is received, a pattern of the emittedsurface-patterned light, and a pattern of the received surface-patternedlight. Also, the processor 1800 may identify a user's gesture based onthe calculated depth of the object.

The processor 1800 may control the gaze tracking sensor 1600 andidentify a point of gaze of a user, by executing the gaze pointidentification module 1750 stored in the storage 1700. The processor1800 may measure a depth of the point of the gaze of the user. Forexample, the processor 1800 may calculate a depth of a point of gaze atwhich a user gazes based on positions of the user's pupils.Alternatively, for example, the processor 1800 may also measure a depthof an object located at a point of gaze of a user by using the depthsensing unit 1500. In this case, the processor 1800 may irradiate lighttoward the object located at the point of the gaze of the user, andmeasure a depth of the point of the gaze by using the light reflectedfrom the object.

Also, the processor 1800 may identify a point of gaze of a user via thegaze tracking sensor 1600, and determine whether a change in a depth ofthe identified point of the gaze is greater than a certain thresholdvalue. The processor 1800 may monitor a change of a depth of a point ofgaze of a user, and determine whether a change in the depth of the pointof the gaze of the user is greater than a certain threshold value. Also,the processor 1800 may determine whether to scan the surroundings of theAR device 1000, according to the change in the depth of the point of thegaze of the user.

FIG. 3 is a block diagram of the depth sensing unit 1500 according to anembodiment.

Referring to FIG. 3 , the depth sensing unit 1500 may include the lightsource unit 1510, the pattern generator 1520, and the light receiver1530.

The light source unit 1510 may include a plurality of light sourceelements, and may irradiate light toward at least a portion of thepattern generator 1520. For example, the light source unit 1510 mayinclude a plurality of arranged laser light emitting elements, and thelight source unit 1510 is positioned at a lower end of the patterngenerator 1520 described below and may irradiate laser light toward thepattern generator 1520.

The pattern generator 1520 may generate a pattern of light irradiatedfrom the light source unit 1510. Patterned light may be emitted from thepattern generator 1520 while the light irradiated from the light sourceunit 1510 passes through the pattern generator 1520.

The pattern generator 1520 may include a dot-patterned light generationarea for changing light irradiated from the light source unit 1510 todot-patterned light and a surface-patterned light generation area forchanging light irradiated from the light source unit 1510 tosurface-patterned light. Also, the dot-patterned light generation areaand the surface-patterned light generation area may each be divided intoa plurality of sub-areas.

The pattern generator 1520 may include, for example, a DOE, or mayinclude an LC lens array. When the pattern generator 1520 includes aDOE, the pattern generator 1520 may be manufactured to include adot-patterned light generation area and a surface-patterned lightgeneration area. Alternatively, when the pattern generator 1520 includesan LC lens array, a certain control voltage is applied to the patterngenerator 1520 by the processor 1800, the arrangement of liquid crystalmolecules in the pattern generator 1520 is changed, and thus, adot-patterned light generation area and a surface-patterned lightgeneration area may be flexibly formed in the pattern generator 1520.

When patterned light emitted from the pattern generator 1520 isreflected from an object, the light receiver 1530 may receive thereflected patterned light.

FIG. 4A is a diagram illustrating an example of surface-patterned lightaccording to an embodiment.

Referring to FIG. 4A, surface-patterned light may be emitted from thedepth sensing unit 1500. Surface-patterned light 40 is patterned lightemitted toward an entire area including an object, and for example, maybe emitted toward an entire area including an object without an areaomitted from the area including the object.

FIG. 4B is a diagram illustrating an example of dot-patterned lightaccording to an embodiment.

Referring to FIG. 4B, dot-patterned light may be emitted from the depthsensing unit 1500. Dot-patterned light 42 is patterned light emittedtoward a partial area within an area including an object, and mayinclude, for example, pieces of dot-shaped light spaced apart from eachother by a certain distance.

FIG. 5A is a diagram illustrating an example in which light irradiatedfrom the light source unit 1510 is changed to dot-patterned light by thepattern generator 1520 according to an embodiment.

Referring to FIG. 5A, while light irradiated from a partial area 50 ofthe light source unit 1510 passes through a dot-patterned lightgeneration area 52 of the pattern generator 1520, dot-patterned lightmay be emitted toward a real space.

FIG. 5B is a diagram illustrating an example in which light irradiatedfrom the light source unit 1510 is changed to surface-patterned light bythe pattern generator 1520 according to an embodiment.

Referring to FIG. 5B, while light irradiated from a partial area 54 ofthe light source unit 1510 passes through a surface-patterned lightgeneration area 56 of the pattern generator 1520, surface-patternedlight may be emitted toward a real space.

FIG. 6 is a diagram illustrating a matching relationship betweensub-areas of the pattern generator 1520 and areas of a real spaceaccording to an embodiment.

Referring to FIG. 6 , a dot-patterned light generation area fordot-patterned light in the pattern generator 1520 may be divided into asub-area a, a sub-area b, a sub-area c, a sub-area d, and a sub-area e.Also, the sub-area a of the pattern generator 1520 may correspond to anarea A of the real space, the sub-area b of the pattern generator 1520may correspond to an area B of the real space, the sub-area c of thepattern generator 1520 may correspond to an area C of the real space,the sub-area d of the pattern generator 1520 may correspond to an area Dof the real space, and the sub-area e of the pattern generator 1520 maycorrespond to an area E of the real space.

Thus, dot-patterned light may be emitted toward the area A of the realspace while light irradiated from the light source unit 1510 passesthrough the sub-area a, dot-patterned light may be emitted toward thearea B of the real space while the light irradiated from the lightsource unit 1510 passes through the sub-area b, dot-patterned light maybe emitted toward the area C of the real space while the lightirradiated from the light source unit 1510 passes through the sub-areac, dot-patterned light may be emitted toward the area D of the realspace while the light irradiated from the light source unit 1510 passesthrough the sub-area d, and dot-patterned light may be emitted towardthe area E of the real space while the light irradiated from the lightsource unit 1510 passes through the sub-area e.

FIG. 7A is a diagram illustrating an example of emitting dot-patternedlight through one sub-area among the sub-areas of the pattern generator1520 according to a position of an object, according to an embodiment.

Referring to FIG. 7A, when the object for which depth is to be measuredis included in the area A of the real space, the AR device 1000 may emitdot-patterned light only through the sub-area a among the sub-areas ofthe pattern generator 1520.

In this case, the AR device 1000 activates a partial area of the lightsource unit 1510 corresponding to the sub-area a of the patterngenerator 1520, and light irradiated from the activated partial areapasses through the sub-area a of the pattern generator 1520, and thus,the dot-patterned light may be emitted from the sub-area a of thepattern generator 1520 toward the area A of the real space. Also, thedot-patterned light emitted toward the area A of the real space isreflected from the object, and the reflected dot-patterned light isreceived by the light receiver 1530, and thus, the AR device 1000 maymeasure the depth of the object,

FIG. 7B is a diagram illustrating an example of emitting dot-patternedlight through two sub-areas among the sub-areas of the pattern generator1520 according to a position of an object, according to an embodiment.

Referring to FIG. 7B, when the object for which depth is to be measuredis included in the areas A and C of the real space, the AR device 1000may emit dot-patterned light only through the sub-areas a and c amongthe sub-areas of the pattern generator 1520.

In this case, the AR device 1000 activates partial areas of the lightsource unit 1510 corresponding to the sub-areas a and c of the patterngenerator 1520, and light irradiated from the activated partial areaspasses through the sub-areas a and c of the pattern generator 1520, andthus, the dot-patterned light may be emitted from the sub-areas a and cof the pattern generator 1520 toward the areas A and C of the realspace.

Also, the dot-patterned light emitted toward the areas A and C of thereal space is reflected from the object, and the reflected dot-patternedlight is received by the light receiver 1530, and thus, the AR device1000 may measure the depth of the object.

The AR device 1000 may emit dot-patterned light only with respect to apartial area of a real space in which an object is located, and thus, anamount of power consumed by the AR device 1000 to measure a depth of theobject may be reduced.

FIG. 8 is a flowchart of a method, performed by the AR device 1000, forselectively emitting dot-patterned light and surface-patterned light,according to an embodiment.

In operation S800, the AR device 1000 may determine whether to emitdot-patterned light. The AR device 1000 may determine whether to emitdot-patterned light or surface-patterned light based on a distancebetween an object for which depth is to be measured and the AR device1000.

The AR device 1000 according to an embodiment of the disclosure maydetermine to emit dot-patterned light when a distance between the ARdevice 1000 and an object where a point of gaze of a user is directed isgreater than or equal to a certain threshold value. For example, the ARdevice 1000 may identify a depth of a point of gaze of a user by usingthe gaze tracking sensor 1600, and determine to emit dot-patterned lightwhen the depth of the point of the gaze of the user is greater than athreshold value. Also, for example, the AR device 1000 may identify adepth of a point of gaze of a user by using the gaze tracking sensor1600, and determine to emit surface-patterned light when the depth ofthe point of gaze of the user is less than a threshold value.

Alternatively, for example, the AR device 1000 may first measure a depthof a certain area in the vicinity of a position where a point of gaze ofa user is directed, and determine to emit dot-patterned light when themeasured depth is greater than a threshold value. Also, for example, theAR device 1000 may first measure a depth of a certain area in thevicinity of a position where a point of gaze of a user is directed, anddetermine to emit surface-patterned light when the measured depth isless than a threshold value.

The AR device 1000 according to an embodiment of the disclosure maydetermine to emit dot-patterned light when it is necessary to scan thesurroundings of the AR device 1000. For example, when the AR device 1000is powered on, the AR device 1000 may determine to emit dot-patternedlight in order to generate a depth map for neighboring objects. Also,for example, when a depth of a point of gaze of a user significantlychanges to be greater than or equal to a certain threshold value, the ARdevice 1000 may determine to emit dot-patterned light in order togenerate a depth map for neighboring objects.

When it is necessary to identify an input of a user's gesture, the ARdevice 1000 according to an embodiment of the disclosure may determineto emit surface-patterned light. For example, when a certain gestureaction by a user's hand is detected, the AR device 1000 may determine toemit surface-patterned light in order to receive an input of a gestureof the user's hand.

When it is determined to emit the dot-patterned light in operation S800,the AR device 1000 may identify the light source unit 1510 correspondingto a dot-patterned light generation area of the pattern generator 1520in operation S805. The pattern generator 1520 may include adot-patterned light generation area for generating dot-patterned lightand a surface-patterned light generation area for generatingsurface-patterned light. Also, the AR device 1000 may identify a portionof the light source unit 1510 corresponding to the dot-patterned lightgeneration area. The portion of the light source unit 1510 correspondingto the dot-patterned light generation area may be a portion thatirradiates light from the light source unit 1510 to the dot-patternedlight generation area.

The AR device 1000 may emit dot-patterned light through the patterngenerator 1520 in operation S810. The AR device 1000 may activate aportion of the light source unit 1510 corresponding to the dot-patternedlight generation area, so that light irradiated from the portion of thelight source unit 1510 may be emitted through the dot-patterned lightgeneration area of the pattern generator 1520. The light emitted throughthe dot-patterned light generation area may be dot-patterned light.

In operation S815, the AR device 1000 may receive dot-patterned lightreflected from an object. The dot-patterned light emitted from thedot-patterned light generation area may be reflected from the object,and the light receiver 1530 of the AR device 1000 may receive thereflected dot-patterned light.

In operation S820, the AR device 1000 may measure a depth of the objectbased on the emitted dot-patterned light and the reflected dot-patternedlight. The AR device 1000 may calculate the depth of the object based ona time when the dot-patterned light is emitted, a time when thereflected dot-patterned light is received, and a difference between apattern of the emitted dot-patterned light and a pattern of the receiveddot-patterned light.

When it is determined not to emit the dot-patterned light in operationS800, the AR device 1000 may identify the light source unit 1510corresponding to the dot-patterned light generation area of the patterngenerator 1520 in operation S825. Also, the AR device 1000 may identifya portion of the light source unit 1510 corresponding to thesurface-patterned light generation area. The portion of the light sourceunit 1510 corresponding to the surface-patterned light generation areamay be a portion that irradiates light from the light source unit 1510to the surface-patterned light generation area.

In operation S830, the AR device 1000 may emit surface-patterned lightthrough the pattern generator 1520. The AR device 1000 may activate aportion of the light source unit 1510 corresponding to thesurface-patterned light generation area, so that light irradiated fromthe portion of the light source unit 1510 may be emitted through thesurface-patterned light generation area of the pattern generator 1520.The light emitted through the surface-patterned light generation areamay be surface-patterned light.

In operation S835, the AR device 1000 may receive surface-patternedlight reflected from an object. The surface-patterned light emitted fromthe surface-patterned light generation area may be reflected from theobject, and the light receiver 1530 of the AR device 1000 may receivethe reflected surface-patterned light.

In operation S840, a depth of the object may be measured based on theemitted surface-patterned light and the reflected surface-patternedlight. The AR device 1000 may calculate the depth of the object based ona time when the surface-patterned light is emitted, a time when thereflected surface-patterned light is received, and a difference betweena pattern of the emitted surface-patterned light and a pattern of thereceived surface-patterned light.

FIG. 9 is a flowchart of a method, performed by the AR device 1000, forsequentially emitting dot-patterned light and surface-patterned light;according to an embodiment.

In FIG. 9 , the AR device 1000 may sequentially emit dot-patterned lightand surface-patterned light in order to scan the surroundings of the ARdevice 1000.

In operation S900, the AR device 1000 may identify a light sourcecorresponding to a dot-patterned light generation area of the patterngenerator 1520, and in operation S905, the AR device 1000 may emitdot-patterned light through the pattern generator 1520. The AR apparatus1000 may activate the identified light source so that light isirradiated from the light source and passes through the dot-patternedlight generation area of the pattern generator 1520. The dot-patternedlight may be emitted from the dot-patterned light generation area to anobject.

Also, in operation S910, the AR device 1000 may receive thedot-patterned light reflected from the object, and in operation S915,the AR device 1000 may generate depth information of the object based onthe emitted dot-patterned light and the received dot-patterned light.

In operation S920, the AR device 1000 may identify a light sourcecorresponding to a surface-patterned light generation area of thepattern generator 1520, and in operation S925, the AR device 1000 mayemit surface-patterned light through the pattern generator 1520. The ARdevice 1000 may activate the identified light source so that light isirradiated from the light source and passes through thesurface-patterned light generation area of the pattern generator 1520.The surface-patterned light may be emitted from the surface-patternedlight generation area to an object.

Also, in operation S930, the AR device 1000 may receive thesurface-patterned light reflected from the object, and in operationS935, the AR device 1000 may generate depth information of the objectbased on the emitted surface-patterned light and the receivedsurface-patterned light.

In operation S940, the AR device 1000 may determine whether to terminatedepth measurement. The AR device 1000 may measure depths of objects inthe vicinity of the AR device 1000, and generate a depth map of thesurroundings of the AR device 1000. When it is determined that the depthmap is not sufficiently generated, the AR device 1000 may repeatedlyperform operations S900 to S935. When it is determined that the depthmap is sufficiently generated, the AR device 1000 may terminate depthmeasurement.

FIG. 10 is a diagram illustrating an example of emitting patterned lightonly in a partial area in the vicinity of a point of gaze of a useraccording to an embodiment.

Referring to FIG. 10 , the AR device 1000 may identify a point of user'sgaze 100, and may set, as a patterned light emission area 110, a partialarea in the vicinity of the point of user's gaze 100 within an area inthe vicinity of the AR device 1000. Also, patterned light may be emittedtoward the set patterned light emission area 110 of the AR device 1000.

FIG. 11 is a flowchart of a method for emitting patterned lightaccording to a depth of a point of gaze of a user, according to anembodiment.

In operation S1100, the AR device 1000 may identify a point of gaze of auser. The AR device 1000 may identify the point of the gaze of the userby using the gaze tracking sensor 1600. The AR device 1000 may measure adepth of the point of the gaze of the user. For example, the AR device1000 may calculate a depth of a point of gaze at which a user gazesbased on positions of the user's pupils. Alternatively, for example, theAR device 1000 may also directly measure a depth of an object located ata point of gaze of a user. In this case, the AR device 1000 mayirradiate light toward the object located at the point of the gaze ofthe user, and measure a depth of the point of the gaze by using thelight reflected from the object.

In operation S1105, the AR device 1000 may determine a type of patternedlight to be emitted based on a depth of the point of gaze. The AR device1000 may determine to emit dot-patterned light when the depth of thepoint of gaze is greater than a certain threshold value. Also, the ARdevice 1000 may determine to emit surface-patterned light when the depthof the point of gaze is less than a certain threshold value. Forexample, a threshold value compared with a depth of a point of gaze maybe a certain distance value in the vicinity of a user's body. Thus, theAR device 1000 may determine to emit surface-patterned light when it isdetermined that the user gazes the surroundings of the user's body.Also, the AR device 1000 may determine to emit dot-patterned light whenit is determined that the user gazes at a zone far from the user.

In operation S1110, the AR device 1000 may determine an emission rangeof the patterned light. The AR device 1000 may determine to emit thepatterned light only for a partial area within an entire area in thevicinity of the AR device 1000 according to a preset criterion. Forexample, the AR device 1000 may determine the emission range of thepatterned light by considering a type of an application being executedand a function of the application. For example, in order to identify theuser's gesture, the AR device 1000 may determine a partial area in thevicinity of the user's hand as an area onto which the patterned light isto be emitted. However, the disclosure is not limited thereto, and forexample, the emission range of the patterned light may be determinedaccording to various criteria such as a remaining battery amount of theAR device 1000, a battery consumption for measuring a depth, and anaccuracy of a depth to be measured.

In operation S1115, the AR device 1000 may select a partial area of thepattern generator 1520 based on the type of the patterned light and theemission range of the patterned light. The AR device 1000 may determinethrough which area of the pattern generator 1520 the patterned lightshould be emitted based on the type of the patterned light and theemission range of the patterned light.

In operation S1120, the AR device 1000 may emit the patterned light byactivating a partial area of the light source unit 1510 corresponding tothe partial area of the pattern generator 1520. The AR device 1000 mayactivate the partial area of the light source unit 1510 that irradiateslight to the partial area of the pattern generator 1520 selected inoperation S1115, and the light irradiated from the partial area of thelight source unit 1510 may pass through the partial area of the patterngenerator 1520 selected in operation S1115. The patterned light that haspassed through the partial area of the pattern generator 1520 may beemitted toward an object.

In operation S1125, the AR device 1000 may receive the patterned lightreflected from the object in the vicinity of the point of gaze, and inoperation S1130, the AR device 1000 may measure a depth of thesurroundings of the point of gaze based on the emitted patterned lightand the reflected patterned light.

FIG. 12 is a diagram illustrating an example of emitting patterned lightin response to a user's gesture being detected according to anembodiment.

Referring to FIG. 12 , the AR device 1000 may detect a gesture of auser's hand, emit surface-patterned light onto an area in the vicinityof (or corresponding to) the user's hand, and emit dot-patterned lightonto the remaining area.

FIG. 13 is a flowchart of a method for emitting patterned light inresponse to a user's gesture being detected according to an embodiment.

In operation S1300, the AR device 1000 may detect a gesture of a user'shand. The user may do a preset motion in order to input a gesture usinga hand, and the AR device 1000 may detect the gesture of the user'shand. The AR device 1000 may monitor the surroundings of the AR device1000 by emitting a small amount of patterned light, and may detect theuser's motion for inputting the gesture.

In operation S1310, the AR device 1000 may emit surface-patterned lighttoward an area in the vicinity of (or corresponding to) the user's hand.The AR device 1000 may determine a certain area in the vicinity of theuser' hand as an area onto which the surface-patterned light is to beemitted, and may emit the surface-patterned light onto the determinedarea. The AR device 1000 emits the surface-patterned light only onto thearea in the vicinity of the user's hand, and thus, may effectivelydetect a gesture of the user's hand while reducing power consumption ofthe AR device 1000.

In operation S1320, the AR device 1000 may emit dot-patterned lighttoward the remaining area. The AR device 1000 may obtain depthinformation about the object in the vicinity of the user while detectingthe gesture of the user's hand by emitting the dot-patterned light ontothe remaining area other than the area in the vicinity of the user'shand in a real space.

FIG. 14 is a flowchart of a method for measuring a depth of thesurroundings of the AR device 1000 according to a change in a depth of apoint of gaze, according to an embodiment.

In operation S1400, the AR device 1000 may determine whether a change ina depth of a point of gaze is greater than a certain threshold value.The AR device 1000 may monitor a change in a depth of a point of gaze ofa user, and may determine whether the change in the depth of the pointof the gaze of the user is greater than a certain threshold value.

When it is determined that the change in the depth of the point of gazeis greater than the certain threshold value, in operation S1410, the ARdevice 1000 may measure a depth of an entire area of a real space. Whenthe change in the depth of the point of the gaze of the user is large,the user may be in a new environment, and thus, the AR device 1000 maymeasure a depth of an entire area of a real space in order to scan thesurroundings of the AR device 1000. The AR device 1000 may emitdot-patterned light toward the surroundings of the AR device 1000, andmay receive the dot-patterned light reflected from an object. Also, theAR device 1000 may measure a depth of the surroundings of the AR device1000 by comparing the emitted dot-patterned light with the receiveddot-patterned light.

When it is determined that the change in the depth of the point of gazeis less than the certain threshold value, in operation S1420, the ARdevice 1000 may measure a depth of an area in the vicinity of the pointof gaze. When the change in the depth of the point of the gaze of theuser is small, the user may be in a new environment, and the AR device1000 may measure only a depth of an area in the vicinity of the point ofthe gaze.

An embodiment of the disclosure may be implemented in the form of arecording medium including instructions, which are capable of beingexecuted by a computer, such as a program module executed by thecomputer. A computer-readable recording medium may be any availablemedium accessible by a computer and may include volatile andnon-volatile media and separable and non-separable media. In addition,the computer-readable recording medium may include a computer storagemedium and a communication medium. The computer storage medium includesvolatile and non-volatile media and separable and non-separable media,which are implemented by any method or technique for storing informationsuch as computer-readable instructions, data structures, programmodules, or other data. The communication medium may typically includecomputer-readable instructions, data structures, or other data in amodulated data signal such as program modules.

Also, a computer-readable storage medium may be provided in the form ofa non-transitory storage medium. Here, the term “non-transitory storagemedium” only means that it is a tangible device and does not includesignals (e.g., electromagnetic waves), and the term does not distinguishbetween a case where data is stored semi-permanently in a storage mediumand a case where data is temporarily stored. For example, the“non-transitory storage medium” may include a buffer in which data istemporarily stored.

According to an embodiment of the disclosure, methods according tovarious embodiments disclosed herein may be provided while included in acomputer program product. The computer program product may be traded asmerchandise between a seller and a purchaser. The computer programproduct may be distributed in the form of a device-readable storagemedium (e.g., a compact disc read only memory (CD-ROM)), or may bedistributed (e.g., downloaded or uploaded) online via an applicationstore (e.g., Play Store™) or between two user devices (e.g.,smartphones) directly. When distributed online, at least part of thecomputer program product (e.g., a downloadable application) may betemporarily generated or at least temporarily stored in adevice-readable storage medium, such as a memory of a manufacturer'sserver, a server of an application store, or a relay server.

In addition, the term such as “ . . . unit” or “ . . . portion” usedherein may refer to a hardware component such as a processor or acircuit, and/or a software component executed by the hardware componentsuch as a processor.

An expression “including at least one of a, b, or c” used herein means“including only a”, “including only b”, “including only c”, “including aand b”, “including b and c”, “including a and c”, or “including both a,b and c”.

It will be understood by one of ordinary skill in the art that theembodiments of the disclosure are provide for illustration and may beimplemented in different ways without departing from the spirit andscope of the disclosure. Therefore, it should be understood that theforegoing embodiments of the disclosure are provided for illustrativepurposes only and are not to be construed in any way as limiting thedisclosure. For example, each component described as a single type maybe implemented in a distributed manner, and likewise, componentsdescribed as being distributed may be implemented as a combined type.

The scope of the disclosure should be defined by the appended claims andequivalent thereof, and any changes or modifications derived from theappended claims and equivalents thereof should be construed as fallingwithin the scope of the disclosure.

The invention claimed is:
 1. A method, by an augmented reality (AR)device, of measuring a depth of an object, the method comprising:determining, from among a dot-pattern and a surface-pattern, a patternof light to be emitted for measuring the depth of the object;identifying, from within an entire area of a pattern generator, apartial area of a light source unit corresponding to an area for thedetermined pattern; emitting light through the area for the determinedpattern, by activating the identified partial area of the light sourceunit; receiving light reflected from the object; and measuring the depthof the object based on the emitted light and the received reflectedlight.
 2. The method of claim 1, wherein the area for the determinedpattern comprises a first area for changing the light irradiated fromthe light source unit to the dot-patterned light or a second area forchanging the light irradiated from the light source unit to thesurface-patterned light.
 3. The method of claim 2, wherein the firstarea comprises a plurality of first sub-areas, and wherein the pluralityof first sub-areas respectively correspond to a plurality of real areasof a real space.
 4. The method of claim 3, further comprising:identifying a position of the object in the real space; and identifying,from the plurality of first sub-areas, at least one first sub-areacorresponding to the position of the object, wherein light is emittedthrough the identified at least one first sub-area by activating apartial area of the light source unit corresponding to the identified atleast one first sub-area.
 5. The method of claim 1, further comprising:identifying a point of gaze of a user of the AR device; and identifyinga depth of the point of gaze, wherein the determining of the patterncomprises selecting based on the depth of the point of gaze, thedot-pattern or the surface-pattern.
 6. The method of claim 5, furthercomprising: identifying a variation in the depth of the point of gaze;and based on the identified variation in the depth of the point of gaze,determining whether to sequentially emit the light of the dot-patter andthe light of the surface-pattern through the pattern generator.
 7. Themethod of claim 5, further comprising based on a position of the pointof gaze, determining, from within an entire area of a real space, acertain area corresponding to the point of gaze, wherein the light isemitted through an area of the pattern generator corresponding to thedetermined certain area.
 8. The method of claim 1, further comprising:detecting a gesture of a user's hand; determining to emit the light ofthe surface-pattern onto an area corresponding to the user's hand withina real space; and determining to emit the light of the dot-pattern ontoa remaining area within the real space, the remaining area being an areawithin the real space that does not correspond to the user's hand. 9.The method of claim 1, wherein the light irradiated from the lightsource unit of the AR device toward the pattern generator is changed toa light of a pattern through the pattern generator.
 10. The method ofclaim 1, wherein the pattern generator comprises at least one of adiffractive optical element (DOE) or a liquid crystal (LC) lens array.11. An augmented reality (AR) device for measuring a depth of an object,the AR device comprising: a light source unit configured to irradiatelight for depth measurement; a pattern generator configured to changethe irradiated light to patterned light; a light receiver configured toreceive light reflected from an object in a vicinity of the AR device; amemory storing instructions; and a processor configured to execute theinstructions to: determine, from among a dot-pattern and asurface-pattern, a pattern of light to be emitted for measuring thedepth of the object, identify, from within an entire area of the patterngenerator, a partial area of the light source unit corresponding to anarea for the determined pattern, emit light through the area for thedetermined pattern, by activating the identified partial area of thelight source unit, receive, through the light receiver, light reflectedfrom the object, and measure the depth of the object based on theemitted light and the received reflected light.
 12. The AR device ofclaim 11, wherein the pattern generator comprises a first area forchanging the light irradiated from the light source unit to light of thedot-pattern and a second area for changing the light irradiated from thelight source unit to light of the surface-pattern.
 13. The AR device ofclaim 12, wherein the first area comprises a plurality of firstsub-areas, and the plurality of first sub-areas respectively correspondto a plurality of real areas of a real space.
 14. The AR device of claim13, wherein the processor is further configured to execute theinstructions to identify a position of the object in the real space, andidentify, from the plurality of first sub-areas, at least one firstsub-area corresponding to the position of the object, and wherein thelight is emitted through the identified at least one first sub-area byactivating a partial area of the light source unit corresponding to theidentified at least one first sub-area.
 15. A non-transitorycomputer-readable recording medium having recorded thereon a program forexecuting the method of claim 1 on a computer.